Stock-Based Compensation - Stock Options Outstanding Additional Information (Detail) (USD $)	12 Months Ended
Dec. 31, 2012
Schedule Of Stock Options [Line Items]
Outstanding Options, Shares	63,171,918
Outstanding Options, Weighted average remaining contractual Life (Years)	4 years 10 months 24 days
Weighted Average Exercisable Price, Outstanding	$ 28.83
Exercisable Options, Shares	50,671,654
Exercisable Options, weighted- Average Exercisable Price	$ 30.12
Exercise Prices Range $11.02-$15.00 [Member]
Schedule Of Stock Options [Line Items]
Lower range limit of Exercise Prices	$ 11.02
Upper range limit of Exercise Prices	$ 15.00
Outstanding Options, Shares	6,877,581
Outstanding Options, Weighted average remaining contractual Life (Years)	6 years 1 month 6 days
Weighted Average Exercisable Price, Outstanding	$ 11.39
Exercisable Options, Shares	3,922,950
Exercisable Options, weighted- Average Exercisable Price	$ 11.37
Exercise Prices Range $15.01-$20.00 [Member]
Schedule Of Stock Options [Line Items]
Lower range limit of Exercise Prices	$ 15.01
Upper range limit of Exercise Prices	$ 20.00
Outstanding Options, Shares	186,439
Outstanding Options, Weighted average remaining contractual Life (Years)	3 years 8 months 12 days
Weighted Average Exercisable Price, Outstanding	$ 19.35
Exercisable Options, Shares	171,651
Exercisable Options, weighted- Average Exercisable Price	$ 19.47
Exercise Prices Range $20.01-$25.00 [Member]
Schedule Of Stock Options [Line Items]
Lower range limit of Exercise Prices	$ 20.01
Upper range limit of Exercise Prices	$ 25.00
Outstanding Options, Shares	4,241,644
Outstanding Options, Weighted average remaining contractual Life (Years)	7 years 1 month 6 days
Weighted Average Exercisable Price, Outstanding	$ 23.82
Exercisable Options, Shares	1,831,981
Exercisable Options, weighted- Average Exercisable Price	$ 23.79
Exercise Prices Range $25.01-$30.00 [Member]
Schedule Of Stock Options [Line Items]
Lower range limit of Exercise Prices	$ 25.01
Upper range limit of Exercise Prices	$ 30.00
Outstanding Options, Shares	17,691,503
Outstanding Options, Weighted average remaining contractual Life (Years)	5 years 4 months 24 days
Weighted Average Exercisable Price, Outstanding	$ 29.05
Exercisable Options, Shares	10,591,999
Exercisable Options, weighted- Average Exercisable Price	$ 29.36
Exercise Prices Range $30.01-$35.00 [Member]
Schedule Of Stock Options [Line Items]
Lower range limit of Exercise Prices	$ 30.01
Upper range limit of Exercise Prices	$ 35.00
Outstanding Options, Shares	24,669,720
Outstanding Options, Weighted average remaining contractual Life (Years)	4 years 2 months 12 days
Weighted Average Exercisable Price, Outstanding	$ 31.69
Exercisable Options, Shares	24,648,451
Exercisable Options, weighted- Average Exercisable Price	$ 31.69
Exercise Prices Range $35.01-$36.25 [Member]
Schedule Of Stock Options [Line Items]
Lower range limit of Exercise Prices	$ 35.01
Upper range limit of Exercise Prices	$ 36.25
Outstanding Options, Shares	9,505,031
Outstanding Options, Weighted average remaining contractual Life (Years)	4 years
Weighted Average Exercisable Price, Outstanding	$ 36.06
Exercisable Options, Shares	9,504,622
Exercisable Options, weighted- Average Exercisable Price	$ 36.06

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Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

+ References

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- Definition

The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph 64

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(1)(c)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(iii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(i)-(ii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(1)(a, b)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

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- Definition

Weighted average remaining contractual term of outstanding stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

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